这比不使用任何索引的两个表扫描的嵌套循环连接要快得多。
This is a lot faster than a nested loop join of two table scans without any index usage.
QB 1中三个表用嵌套循环(NLJ)连接。
连接计划指示，强制优化器使用指定的连接方法来连接查询中的表，要么是嵌套循环连接、分类合并连接，要么是动态哈希连接。
Join plan directives that force optimizer to use the designated join method to join tables in the query, either nested loop join, sort merge join, or dynamic hash join.
以上示例展示了如何使用连续扫描和索引来进行数据检索，以及如何使用嵌套循环连接方法来连接所有表。
The above example shows that sequential scan and indexes are used to do the data retrieval, and the nested-loop join method is used to join all tables.
以上示例展示了如何使用连续扫描和索引来进行数据检索，以及如何使用嵌套循环连接方法来连接所有表。
The above example shows that sequential scan and indexes are used to do the data retrieval, and the nested-loop join method is used to join all tables.
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